BIOM Chapter 7
Release of ACh at parasympathetic effectors is always stimulatory. T/F
FALSE
Destruction of astrocytes would decrease the rate at which action potentials are transmitted. T/F
False
During the absolute refractory period, a supramaximal stimulus can bring the cell to threshold. T/F
False
Most brain tumors in adults are found within neurons. T/F
False
Nicotinic receptors utilize G-proteins to regulate the opening of ion channels. T/F
False
The greater the number of depolarization regions on an axon, the faster the action potential will be conducted. T/F
False
The most abundant neuropeptide in the brain is ________. A) neuropeptide Y B) neuropeptide Z C) substance P D) CCK
A) neuropeptide Y
Relaxation of cerebral blood vessels would be stimulated by excessive ________ activity. A) nitric oxide B) acetylcholine C) norepinephrine D) glutamate
A) nitric oxide
Addictive drugs, as well as nicotine, activate dopamine release in the ________. A) nucleus accumbens B) corpus striatum C) basal nuclei D) corpus callosum
A) nucleus accumbens
Structural classifications of neurons do NOT include ________. A) motor neurons B) bipolar neurons C) multipolar neurons D) pseudounipolar neurons
A) motor neurons
The term "white matter" refers to ________. A) myelinated axons in the CNS B) myelinated axons in the PNS C) nonmyelinated cell bodies and dendrites in the CNS D) nonmyelinated axons in the CNS
A) myelinated axons in the CNS
Which division of the nervous system innervates involuntary effectors? A) Central nervous system B) Somatic nervous system C) Autonomic nervous system D) Associative nervous system
C) Autonomic nervous system
Both long-term potentiation and long-term depression require the release of ________ from the postsynaptic neuron membrane. A) Cl- B) K+ C) Ca2+ D) Mg2+
C) Ca2+
The membrane of resting nerve cells is more permeable to ________ ions than ________ ions. A) sodium, potassium B) calcium, potassium C) potassium, sodium D) chloride, potassium
C) potassium, sodium
Which gas(es) can function as a neurotransmitter? A) carbon dioxide B) nitric oxide C) carbon monoxide D) Both nitric oxide and carbon monoxide
D) Both nitric oxide and carbon monoxide
The period of time when Na+ channels are recovering from their inactive state and K+ channels are still open is the ________. A) repolarization B) absolute refractory period C) relative refractory period D) Both repolarization and relative refractory period are correct.
D) Both repolarization and relative refractory period are correct.
What type of proteins are present at chemical synapses to ensure the close proximity of the presynaptic and postsynaptic membranes? A) Connexins B) Myelin C) Terminal boutons D) Cell adhesion molecules (CAMs)
D) Cell adhesion molecules (CAMs)
What type of proteins are present in gap junctions that form water-filled channels between neurons? A) Connexins B) Myelin C) Terminal boutons D) Cell adhesion molecules (CAMs)
D) Cell adhesion molecules (CAMs)
The most common neurotransmitter in the brain is ________. A) glycine B) acetylcholine C) serotonin D) GABA
D) GABA
What is NOT true of conduction through dendrites and cell bodies of neurons? A) It creates EPSPs. B) It is spread by cable properties. C) EPSPs can summate to reach threshold. D) It generates action potentials in the cell body.
D) It generates action potentials in the cell body.
A patient with Parkinson disease will have difficulty initiating skeletal muscle movements because the nigrostriatal dopamine system, degenerated in Parkinson disease, is part of the primary motor cortex. T/F
FALSE
A lack of extracellular Ca2+ would cause increased release of neurotransmitters. T/F
False
All axons in the PNS have a myelin sheath. T/F
False
An inactivated ion channel will respond to a stronger than normal threshold stimulus. T/F
False
Both neurons and neuroglia will easily divide by mitosis. T/F
False
Since diffusion of ions down their concentration gradients is a passive process, ATP does not influence the ability of a cell to be depolarized and repolarized. T/F
False
Somatic motor neurons innervate involuntary effectors. T/F
False
The blood-brain barrier prevents hydrophobic molecules from diffusing into the brain. T/F
False
Glycine and GABA act as inhibitory neurotransmitters in the CNS because they bind to Cl- channels on the postsynaptic membrane. T/F
TRUE
Norepinephrine binding to a receptor stimulates the activity of adenylate cyclase. T/F
TRUE
Parkinson disease is associated with the loss of dopaminergic neurons. T/F
TRUE
Excitotoxicity is caused by ________. A) insufficient synaptic release of glutamate B) excessive synaptic release of glutamate C) GABA inhibition D) insufficient synaptic release of ACh
B) excessive synaptic release of glutamate
Synaptic plasticity involves structural changes in neurons, such as ________. A) formation of axillary branches B) formation of dendritic spines C) formation of more axon terminals D) mitosis of neurons
B) formation of dendritic spines
Excitatory postsynaptic potentials are produced in the brain primarily by ________. A) glycine B) glutamic acid C) gamma-aminobutyric acid D) benzodiazepines
B) glutamic acid
What is the action of the binding of muscarine to its receptors in the digestive system? A) Alpha subunits bind to K+ channels, close them, leading to depolarization. B) Alpha subunits bind to K+ channels, open them, leading to hyperpolarization. C) Beta-gamma subunits bind to K+ channels, close them, leading to depolarization. D) Beta-gamma subunits bind to K+ channels, open them, leading to hyperpolarization.
A) Alpha subunits bind to K+ channels, close them, leading to depolarization.
Which of the following is NOT true of long-term potentiation (LTP)? A) Associated with the removal of AMPA glutamate receptors B) Repeated stimulation enhance excitability C) Associated with insertion of AMPA glutamate receptors D) It is a form of synaptic plasticity
A) Associated with the removal of AMPA glutamate receptors
Benzodiazepines act by increasing ________ activity. A) GABA B) glutamate C) ACh D) enkephalin
A) GABA
Which type of cell of the CNS is phagocytic? A) Microglia B) Satellite cells C) Ependymal cells D) Oligodendrocytes
A) Microglia
What is NOT true of the relative refractory period? A) Na+ channels are inactivated. B) Many Na+ channels are returning to a closed state. C) K+ is moving out of the axon through its open channels. D) A strong stimulus could cause a depolarization.
A) Na+ channels are inactivated.
What type of autonomic fibers release ACh at effectors? A) Parasympathetic B) Sympathetic C) Somatic D) Sensory
A) Parasympathetic
The myelin sheaths of PNS neurons are produced by ________. A) Schwann cells B) oligodendrocytes C) ependymal cells D) leukocytes
A) Schwann cells
What neurotransmitter is used by neurons with cell bodies in the raphe nuclei along the midline of the brainstem? A) Serotonin B) Dopamine C) Glycine D) GABA
A) Serotonin
Which poison inhibits glycine receptors? A) Strychnine B) Curare C) Tetrodotoxin D) All of the choices are correct.
A) Strychnine
94) What is present at the axon hillock that allows the production of action potentials? A) Voltage-gated channels B) Ligand-gated channels C) Muscarinic receptors D) Chemical-gated channels
A) Voltage-gated channels
An axon will depolarize only if the membrane potential reaches between -70mV and -55mV. This follows the ________. A) all-or-none law B) recruitment law C) graduated law D) threshold law
A) all-or-none law
The most numerous of all cells of CNS nervous tissue are the ________. A) astrocytes B) neurons C) Schwann cells D) microglia
A) astrocytes
The synapses which occur between axons of presynaptic cells and dendrites of postsynaptic cells are called ________. A) axodendritic B) axosomatic C) myoneural D) axoaxonic
A) axodendritic
The brain produces lipid neurotransmitters called ________. A) endocannabinoids B) endorphins C) enkephalins D) nitric oxide
A) endocannabinoids
Botulism toxin prevents release of ACh, causing ________. A) flaccid paralysis B) hemiplegia C) spastic paralysis D) None of the choices are correct.
A) flaccid paralysis
Chemical synapses ________. A) have a delayed impulse transmission B) utilize gap junctions C) occur when two nerve cells are in direct contact with each other D) do not require the release of neurotransmitters
A) have a delayed impulse transmission
Enhancing the excitability of a synapse so that transmission is favored along certain pathways is called ________. A) long-term potentiation B) synaptic plasticity C) excitotoxicity D) summation
A) long-term potentiation
Temporal summation ________. A) occurs when a single neuron releases neurotransmitter rapidly B) occurs because of the convergence of many neurons on a single postsynaptic cell C) only involves excitatory postsynaptic potentials D) only involves inhibitory postsynaptic potentials
A) occurs when a single neuron releases neurotransmitter rapidly
Muscarinic ACh receptors are found in all of the following locations EXCEPT ________. A) skeletal muscle B) smooth muscle C) cardiac muscle D) glands
A) skeletal muscle
Axonal transport ________. A) uses molecular motors B) can only transport signals in a retrograde direction C) has two fast and one slow components D) is a passive process
A) uses molecular motors
The average resting membrane potential of an axon is ________. A) −70 mV B) −85 mV C) 0 mV D) +30 mV
A) −70 mV
Muscarinic ACh receptors act through ________ activation of K+ channels. A) cGMP B) G-protein C) M-protein D) ATP
B) G-protein
Exogenous and endogenous opioids have both similar and varying effects. Choose the statement that correctly summarizes their differences. A) Exogenous, but not endogenous, can block transmissions of pain. B) Naloxone has been shown to block the proven actions of both exogenous and endogenous opioids. C) Endogenous are found in the CNS, whereas exogenous are released from neurons in the PNS. D) Like exogenous opioids like morphine, endogenous opioids cause strong feelings of euphoria.
B) Naloxone has been shown to block the proven actions of both exogenous and endogenous opioids.
What do muscarine and nicotine have in common? A) They are both antagonists for their respective receptors. B) They are both agonists for their respective receptors. C) They both activate-protein coupled channels. D) They are both always excitatory.
B) They are both agonists for their respective receptors.
From which amino acid are dopamine, norepinephrine, and epinephrine all derived? A) Histidine B) Tyrosine C) Tryptophan D) Serine
B) Tyrosine
Cholinergic fibers use ________ as the neurotransmitter. A) norepinephrine B) acetylcholine C) dopamine D) serotonin
B) acetylcholine
Sensory neurons ________. A) are multipolar, and carry impulses toward the CNS B) are pseudounipolar, and carry impulses toward the CNS C) are bipolar, and carry impulses away from the CNS D) are multipolar, and carry impulses away from the CNS
B) are pseudounipolar, and carry impulses toward the CNS
Acetylcholine can induce hyperpolarization by ________. A) binding to nicotinic receptors B) binding to muscarinic receptors C) binding to α-adrenergic receptors D) binding to β-adrenergic receptors
B) binding to muscarinic receptors
Neurotransmitter release would be inhibited by ________. A) stimulating repolarization of the axon terminal B) blocking Ca2+ influx in the axon terminal C) blocking repolarization of the axon terminal D) stimulating protein kinase activity
B) blocking Ca2+ influx in the axon terminal
The ________ dopamine system may be involved in emotional reward and drug addiction. A) nigrostriatal B) mesolimbic C) amygdala D) dentate
B) mesolimbic
Acetylcholine usually induces an excitatory postsynaptic potential when binding to ________ receptors and an inhibitory postsynaptic potential when binding to some ________ receptors. A) NMDA; nicotinic B) nicotinic; muscarinic C) muscarinic; NMDA D) muscarinic; nicotinic
B) nicotinic; muscarinic
The gap of exposed axon in the myelin sheath is the ________. A) neurilemma B) node of Ranvier C) sheath of Schwann D) white matter
B) node of Ranvier
Spatial summation ________. A) occurs when a single neuron releases neurotransmitter rapidly B) occurs because of the convergence of many neurons on a single postsynaptic cell C) only involves excitatory postsynaptic potentials D) only involves inhibitory postsynaptic potentials
B) occurs because of the convergence of many neurons on a single postsynaptic cell
The myelin sheaths of CNS neurons are produced by ________. A) Schwann cells B) oligodendrocytes C) ependymal cells D) leukocytes
B) oligodendrocytes
Endocannabinoids are retrograde neurotransmitters, meaning they are ________. A) released from presynaptic neurons and diffuse to the postsynaptic neuron B) released from postsynaptic neurons and diffuse to the presynaptic neuron C) released from presynaptic neurons and diffuse back to the presynaptic cell body D) None of the choices are correct.
B) released from postsynaptic neurons and diffuse to the presynaptic neuron
Conduction of an action potential in a myelinated axon is called ________. A) point to point conduction B) saltatory conduction C) refractory conduction D) cable conduction
B) saltatory conduction
Nitric oxide ________. A) is a chemical messenger activating adenylate cyclase B) stimulates the dilation of blood vessels C) is produced from L-asparagine D) All of the choices are correct.
B) stimulates the dilation of blood vessels
The minimum depolarization needed to open Na+ gates is called the ________. A) repolarization B) threshold C) refractory period D) all-or-none law
B) threshold
Ion channels that open in response to depolarization are called ________. A) ion-gated channels B) voltage-gated channels C) stimulation-gated channels D) potential-gated channels
B) voltage-gated channels
ATP and adenosine can act as neurotransmitters ________. A) when no ACh is available B) when released by adrenergic neurons during sympathetic activation C) after being used for energy by the cell D) All of the choices are correct.
B) when released by adrenergic neurons during sympathetic activation
Which of the following is NOT an action needed for glutamate to open ion channels? A) NMDA receptor must bind to glycine. B) The membrane must be partially depolarized from the action of a different neurotransmitter. C) Cl- must pass through the open channel. D) Mg2+ is released from NMDA channel to open it.
C) Cl- must pass through the open channel.
What type of neural pathway involves one neuron forming synapses with several postsynaptic neurons? A) Convergent B) Oscillating C) Divergent D) Plastic
C) Divergent
Which type of cell lines the ventricles of the brain and help produce cerebrospinal fluid? A) Microglia B) Satellite cells C) Ependymal cells D) Oligodendrocytes
C) Ependymal cells
Which of the following is NOT classified as a catecholamine? A) Norepinephrine B) Epinephrine C) Histamine D) Dopamine
C) Histamine
Where is glycine released? A) In the PNS B) From the motor neurons innervating skeletal muscles C) In the CNS D) At the diaphragm
C) In the CNS
How do neurons code for a greater response? A) Greater amplitude of stimuli B) Greater Na+ concentration gradient C) Increased frequency of stimuli D) More active Na+/K+ pump
C) Increased frequency of stimuli
At what region of the neuron are action potentials first produced? A) Dendrites B) Cell body C) Initial segment of an axon D) Axon hillock
C) Initial segment of an axon
During an action potential ________. A) Na+ efflux causes depolarization B) K+ influx causes repolarization C) Na+ influx causes depolarization D) K+ influx causes after-hyperpolarization
C) Na+ influx causes depolarization
What is needed to return a membrane to its resting membrane potential, with all ions in the correct locations? A) Influx of negatively charged ions into the cell B) Outflow of Na+ ions via passive ion channels C) Na+/K+ pump action D) Outflow of K+ ions via passive ion channels
C) Na+/K+ pump action
A drug that blocked ________ channels would prevent neuron ________. A) K+; depolarization B) Na+; hyperpolarization C) Na+; depolarization D) Ca2+; repolarization
C) Na+; depolarization
What structure, found surrounding PNS axons, is NOT found surrounding CNS axons? A) Nodes of Ranvier B) Myelin sheath C) Neurilemma D) Plasma membrane
C) Neurilemma
Which ion's movement is responsible for repolarization? A) Influx of K+ B) Influx of Na+ C) Outward diffusion of K+ D) Outward diffusion of Na+
C) Outward diffusion of K+
What type of receptors will bind ATP and adenosine? A) Cotransmitter receptors B) Pyrimenergic receptors C) Purinergic receptors D) None of the choices are correct.
C) Purinergic receptors
What is the predominant effect of stimulation of nicotinic-gated channels? A) Stimulation due to outflow of K+ ions B) Inhibition due to outflow of K+ ions C) Stimulation due to influx of Na+ ions D) Inhibition due to influx of Cl- ions
C) Stimulation due to influx of Na+ ions
Choose the incorrect statement regarding EPSPs. A) They are graded responses. B) They are capable of summation. C) They have a refractory period. D) They are initiated by neurotransmitters.
C) They have a refractory period.
Choose the statement that correctly describes the structure or function of dendrites. A) Transmit action potentials away from the cell body B) Are thin extensions of the axon C) Transmit graded electrochemical impulses toward the cell body D) Release neurotransmitters to initiate graded potentials in adjacent cells
C) Transmit graded electrochemical impulses toward the cell body
Action potentials would be conducted most rapidly by ________. A) a 10 mm diameter myelinated axon B) a 10 mm diameter unmyelinated axon C) a 40 mm diameter myelinated axon D) a 40 mm diameter unmyelinated axon
C) a 40 mm diameter myelinated axon
Neostigmine, used to treat myasthenia gravis, blocks the enzyme that degrades ________. This helps treat the disease because ________. A) acetylcholine; it destroys the antibodies that block nicotinic ACh receptors on the motor end plate B) norepinephrine; it increases the amount of acetylcholine available to bind to receptors on the motor end plate C) acetylcholine; it increases the amount of acetylcholine available to bind to receptors on the motor end plate D) nicotine; it destroys the antibodies that block nicotinic ACh receptors on the motor end plate
C) acetylcholine; it increases the amount of acetylcholine available to bind to receptors on the motor end plate
Depolarization of an axon is a positive feedback mechanism because ________. A) as more sodium channels open, the membrane potential decreases B) as more potassium channels open, the membrane potential decreases C) as more sodium diffuses into the axon, the more voltage-gated potassium channels open D) as more sodium diffuses into the axon, the more voltage-gated sodium channels open
C) as more sodium diffuses into the axon, the more voltage-gated potassium channels open
The blood-brain barrier results mostly from the action of ________, a type of neuroglia. A) ependymal cells B) microglia C) astrocytes D) oligodendrocytes
C) astrocytes
Neurotransmitters ________. A) are released by endocytosis B) bind to voltage-gated channels C) bind to chemically regulated channels D) are actively transported across the synaptic cleft
C) bind to chemically regulated channels
In order to prevent a patient from experiencing pain, local anesthetics must ________ in sensory neurons, which would prevent an action potential. A) inhibit the release of acetylcholine B) bind to potassium channels C) bind to sodium channels D) bind to calcium channels
C) bind to sodium channels
Neuroleptics, which are used to treat schizophrenia, are ________. A) dopamine agonists B) ACh antagonists C) dopamine antagonists D) glutamate agonists
C) dopamine antagonists
Mutation of the N-methyl-D-aspartate (NMDA) receptor would affect the ability of ________ to regulate neural function. A) acetylcholine B) epinephrine C) glutamate D) nitric oxide
C) glutamate
Chemicals that stimulate action potentials in postsynaptic cells are called ________. A) hormones B) enzymes C) neurotransmitters D) neurotrophins
C) neurotransmitters
Unlike chemical synapses, electrical synapses ________. A) are the method of connection between adjacent neurons B) allow communication between cells with larger distances between the membranes C) provide adjacent cells with the ability to act in a coordinated fashion D) are not dependent on the movement of ions across a plasma membrane
C) provide adjacent cells with the ability to act in a coordinated fashion
As the intensity of a stimulus increases, more axons will become activated. This process is called ________. A) threshold B) refraction C) recruitment D) None of the choices are correct.
C) recruitment
Cells supporting neuron cell bodies in ganglia are termed ________. A) astrocytes B) ependymal cells C) satellite cells D) Schwann cells
C) satellite cells
Inhibition of neuropeptide Y synthesis would ________. A) induce euphoria B) induce obesity C) stimulate leptin secretion D) inhibit eating
C) stimulate leptin secretion D) inhibit eating
The varied strength of synaptic transmission is called ________. A) spatial summation B) temporal summation C) synaptic plasticity D) EPSP
C) synaptic plasticity
If a cell's membrane is not excitable, this means that ________. A) the cell is a neuron B) the cell cannot be depolarized under any conditions C) the cell cannot vary the permeability of the membrane to specific ions D) the cell does not have a measurable voltage
C) the cell cannot vary the permeability of the membrane to specific ions
A bundle of axons in the CNS is called a ________. A) nerve B) bundle C) tract D) neuron
C) tract
Serotonin is synthesized from the amino acid ________. A) alanine B) glycine C) tryptophan D) serine
C) tryptophan
Retrograde transport ________. A) moves toward the cell body B) moves membranes, vesicles, and viruses C) uses molecular motor proteins of dynein D) All of the choices are correct.
D) All of the choices are correct.
What event(s) could cause presynaptic inhibition? A) Inactivation of Ca2+ channels B) A second neuron causes a reduction in neurotransmitter release from another neuron C) Removal of SNARE complexes D) All of the choices are correct.
D) All of the choices are correct.
Which of the following are natural analgesics? A) Endorphins B) Enkephalins C) Dynorphins D) All of the choices are correct.
D) All of the choices are correct.
Synaptic transmission using acetylcholine would be disrupted by ________. A) curare B) botulinum toxin C) strychnine D) Both curare and botulinum toxin are correct.
D) Both curare and botulinum toxin are correct.
Hyperpolarization in the postsynaptic cell is caused by ________. A) excitatory postsynaptic potentials B) inhibitory postsynaptic potentials C) movement of K+ out of the cell D) Both inhibitory postsynaptic potentials and movement of K+ out of the cell are correct.
D) Both inhibitory postsynaptic potentials and movement of K+ out of the cell are correct.
What type of neuron is found entirely in the CNS? A) Sensory neuron B) Interneuron C) Association neuron D) Both interneuron and association neuron are correct.
D) Both interneuron and association neuron are correct.
Choose the incorrect statement about norepinephrine. A) It is released in both the central and peripheral nervous systems. B) It is released by sympathetic neurons to smooth muscle, cardiac muscle, and glands. C) Norepinephrine pathways are stimulated by amphetamines. D) It is released from adrenergic neurons in the parasympathetic nervous system.
D) It is released from adrenergic neurons in the parasympathetic nervous system.
Since the action potential "leaps" from node to node in a myelinated axon, ________. A) myelinated axons need far less Na+ channels than unmyelinated axons B) action potentials move faster if the nodes are farther apart C) Na+ movement within the myelin sheath is possible D) Na+ channels are not present between the nodes
D) Na+ channels are not present between the nodes
What action would produce an IPSP on the postsynaptic membrane? A) Influx of Na+ ions B) Opening of Ca2+ channels into the neuron C) Outflow of K+ ions D) Opening of Cl- channels into the neuron
D) Opening of Cl- channels into the neuron
Synaptic vesicles are docked to the plasma membrane of the axon terminal by a protein complex called ________. A) boutons B) connexins C) synaptotagmins D) SNARE
D) SNARE
Action potential transmission in the PNS is decreased if which cells are damaged? A) Astrocytes B) Microglia C) Oligodendrocytes D) Schwann cells
D) Schwann cells
Histamine is able to ________. A) act as a neurotransmitter to cause skeletal muscle contraction B) act as a hormone that inhibits gastric secretion C) act as a neurotransmitter in the brain to cause drowsiness D) act as a regulator in inflammation and allergies
D) act as a regulator in inflammation and allergies
Neurotransmitter action could be prevented, or disrupted, if a drug or other agent ________. A) increased the expression of CAMs in the postsynaptic membrane B) decreased the distance between the pre- and postsynaptic membranes C) decreased the concentration of SNARE complexes in the postsynaptic cell D) blocked voltage-gated Ca2+ channels in the presynaptic membrane
D) blocked voltage-gated Ca2+ channels in the presynaptic membrane
Astrocytes are NOT involved in ________. A) uptake of NT from a synapse B) stimulation or inhibition neurons C) formation of synapses in the CNS D) breakdown and engulfment of foreign material in the CNS E) formation the blood-brain barrier
D) breakdown and engulfment of foreign material in the CNS
Acetylcholine ________. A) is always an excitatory neurotransmitter B) can bind to adrenergic receptors C) is an inhibitory neurotransmitter released by motor neurons D) can bind to nicotinic receptors
D) can bind to nicotinic receptors
A patient is prescribed an MAO inhibitor by their doctor. Knowing the actions of MAO inhibitors, this patient's diagnosis may be ________. A) hypertension, since MAO inhibitors block the release of norepinephrine from sympathetic axons B) hypertension, since MAO inhibitors block the degradation of norepinephrine at the synapse C) depression, since MAO inhibitors block the binding of serotonin to postsynaptic cells D) depression, since MAO inhibitors block the degradation of serotonin at the synapse
D) depression, since MAO inhibitors block the degradation of serotonin at the synapse
Degeneration of spinal motor neurons in adults may be due to a lack of ________ factor. A) brain-derived neurotrophic (BDNF) B) neurotrophin-3 C) nerve growth (NGF) D) glial-derived neurotrophic (GDNF)
D) glial-derived neurotrophic (GDNF)
Catecholamines activate postsynaptic cells by ________. A) inhibition of adenylate cyclase B) increased Ca2+ influx into the target cell C) inhibition of calmodulin D) increased production of cyclic AMP
D) increased production of cyclic AMP
Cocaine is particularly dangerous for patients with cardiovascular disease, or hypertension, because ________. A) it blocks the reuptake of serotonin and dopamine, causing excessive bouts of euphoria B) it inhibits the degradation of norepinephrine, causing coronary artery constriction C) it blocks membrane sodium channels, causing increased EPSPs D) it blocks the reuptake of norepinephrine, causing increased heart rate
D) it blocks the reuptake of norepinephrine, causing increased heart rate
Axonal regeneration is inhibited by ________. A) brain-derived neurotrophic factor B) nerve growth factor C) neurotrophin-3 D) myelin-associated inhibitory protein
D) myelin-associated inhibitory protein
Curare is a competitive ACh antagonist at ________ ACh receptors. A) muscarinic B) NMDA C) kainate D) nicotinic
D) nicotinic
Neurotrophins are NOT responsible for ________. A) maintaining sympathetic ganglion B) sustaining neurons that use the NT dopamine C) embryonic development of neurons D) regeneration of injured motor neurons
D) regeneration of injured motor neurons
The capacity of synapses for alteration at the molecular level is termed ________. A) synaptic modulation B) synaptic alteration C) synaptic capacitance D) synaptic plasticity
D) synaptic plasticity
If the binding of muscarine to its receptor in the heart causes the beta-gamma complex of the G-protein to bind to a K+ channel, ________. A) the K+ channel will close, leading to depolarization B) the K+ channel will open, leading to depolarization C) the K+ channel will close, leading to hyperpolarization and inhibition D) the K+ channel will open, leading to hyperpolarization and inhibition
D) the K+ channel will open, leading to hyperpolarization and inhibition
Both excitatory and inhibitory postsynaptic potentials undergo summation. T/F
T
CCK (cholecystokinin) may act as a neurotransmitter in the brain to promote feelings of satiety. T/F
T
An EPSP is conducted in a decremental fashion to the axon hillock, where voltage-gated Na+ and K+ channels are opened. This creates an action potential in the first segment of the axon. T/F
True
An inhibitory postsynaptic potential could be produced by a neurotransmitter that opens Cl- channels. T/F
True
Atropine is an agonist to nicotine. T/F
True
Both depolarization and repolarization are produced by the diffusion of ions down their concentration gradient. T/F
True
Conduction without decrement means that action potentials transmitted down an axon will not decrease in amplitude. T/F
True
Ganglia are clusters of nerve cell bodies located in the peripheral nervous system. T/F
True
Retrograde axonal transport may be responsible for movement of herpes virus, rabies virus, and tetanus toxin from nerve terminals to the cell body. T/F
True
Since sensory neurons for muscle position are the fastest conducting neurons, they would have a larger diameter than sensory neurons for touch, pain or pressure. T/F
True
The nicotinic ACh receptor is a ligand-gated channel. T/F
True
